Yun-xiao Chong, T. Huang, Feng-Min Li, Guang Liu, Qianli Wu
{"title":"Editorial: Water recycling and low-carbon development","authors":"Yun-xiao Chong, T. Huang, Feng-Min Li, Guang Liu, Qianli Wu","doi":"10.2166/wrd.2021.002","DOIUrl":"https://doi.org/10.2166/wrd.2021.002","url":null,"abstract":"","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":"58 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41305435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haoxiang Yin, Jun Li, H. Yan, Hanying Cai, Yanjian Wan, Gang Yao, Yong Guo, B. Lai
The effect of peroxymonosulfate (PMS) activated by nanocrystalline CuCo2O4 (NPS) on removal of atrazine (ATZ) was studied. First, the main experimental parameters were studied, including CuCo2O4 dose, PMS dose, initial pH value, and co-existing ion. The removal of ATZ (>99%) was attained under the optimal conditions (i.e., 150 mg/L CuCo2O4, 0.2 mM PMS, 5 mg/L ATZ, initial pH value of 6.8, and reaction time of 30 min). However, the removal of ATZ only reached 20.9% in the PMS alone system and there was no significant ATZ removal when adding CuCo2O4 alone into the solution, proving the good performance of the CuCo2O4/PMS system. Furthermore, reusability of CuCo2O4 was tested through five consecutive runs. To confirm which main active radicals were responsible in the system, two radical quenching experiments were carried out and electron paramagnetic resonance (EPR) was tested. In addition, the characterization of fresh and reacted CuCo2O4 NPs was tested by SEM, TEM, EDS, XRD, and XPS. Subsequently, based on the characterization of CuCo2O4 NPs and identification of radicals, ≡Cu2+/ ≡ Cu+ and ≡Co3+/ ≡ Co2+ were considered to be the main catalytic species, while the synergistic effect of Cu and Co played a crucial role. Finally, the degradation pathway of ATZ was proposed.
{"title":"Activation of peroxymonosulfate by CuCo2O4 nano-particles towards long-lasting removal of atrazine","authors":"Haoxiang Yin, Jun Li, H. Yan, Hanying Cai, Yanjian Wan, Gang Yao, Yong Guo, B. Lai","doi":"10.2166/wrd.2021.046","DOIUrl":"https://doi.org/10.2166/wrd.2021.046","url":null,"abstract":"\u0000 The effect of peroxymonosulfate (PMS) activated by nanocrystalline CuCo2O4 (NPS) on removal of atrazine (ATZ) was studied. First, the main experimental parameters were studied, including CuCo2O4 dose, PMS dose, initial pH value, and co-existing ion. The removal of ATZ (>99%) was attained under the optimal conditions (i.e., 150 mg/L CuCo2O4, 0.2 mM PMS, 5 mg/L ATZ, initial pH value of 6.8, and reaction time of 30 min). However, the removal of ATZ only reached 20.9% in the PMS alone system and there was no significant ATZ removal when adding CuCo2O4 alone into the solution, proving the good performance of the CuCo2O4/PMS system. Furthermore, reusability of CuCo2O4 was tested through five consecutive runs. To confirm which main active radicals were responsible in the system, two radical quenching experiments were carried out and electron paramagnetic resonance (EPR) was tested. In addition, the characterization of fresh and reacted CuCo2O4 NPs was tested by SEM, TEM, EDS, XRD, and XPS. Subsequently, based on the characterization of CuCo2O4 NPs and identification of radicals, ≡Cu2+/ ≡ Cu+ and ≡Co3+/ ≡ Co2+ were considered to be the main catalytic species, while the synergistic effect of Cu and Co played a crucial role. Finally, the degradation pathway of ATZ was proposed.","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49043481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work reports the effects of five pipe materials on reverse osmosis (RO)-reclaimed water quality in a large pilot-scale distribution system. These materials includes cast iron (CI), cast iron with cement-mortar lining (CML), stainless steel (SS), PVC, and PE. Long-term running tests for 96 hours are conducted with water quality parameters monitored online and analyzed offline. The results showed that red water appeared in CI pipe due to iron corrosion. The pH and TDS increased during the long-term test. Alkali–silica reaction in CML pipe led to a high increase of pH from 6.3 to 11.4, and TDS from 51 to 230 mg/L. Water quality deterioration was not observed in SS, PVC, and PE pipes. Residual chlorine decay occurred in all the five material pipes with the decay rate order of CI ≫ CML > SS ≈ PVC ≈ PE. Ion concentration variation was also followed during the tests. Fe and Mn ions were detected in CI pipe and Ca, Si, Al, and S were detected in CML pipe. No detectable ion release was found in SS, PVC, and PE pipes. A kinetic model was postulated for the detected ion release with the mechanisms discussed in-depth.
{"title":"Water quality deterioration of reclaimed water produced by reverse osmosis process in large pilot-scale distribution systems of different pipe materials","authors":"Xiyan Xu, Yong Cui, Zhangqing Wang, Hongyu Zhang, Caifeng Li, Kanghua Yu","doi":"10.2166/wrd.2021.042","DOIUrl":"https://doi.org/10.2166/wrd.2021.042","url":null,"abstract":"\u0000 This work reports the effects of five pipe materials on reverse osmosis (RO)-reclaimed water quality in a large pilot-scale distribution system. These materials includes cast iron (CI), cast iron with cement-mortar lining (CML), stainless steel (SS), PVC, and PE. Long-term running tests for 96 hours are conducted with water quality parameters monitored online and analyzed offline. The results showed that red water appeared in CI pipe due to iron corrosion. The pH and TDS increased during the long-term test. Alkali–silica reaction in CML pipe led to a high increase of pH from 6.3 to 11.4, and TDS from 51 to 230 mg/L. Water quality deterioration was not observed in SS, PVC, and PE pipes. Residual chlorine decay occurred in all the five material pipes with the decay rate order of CI ≫ CML > SS ≈ PVC ≈ PE. Ion concentration variation was also followed during the tests. Fe and Mn ions were detected in CI pipe and Ca, Si, Al, and S were detected in CML pipe. No detectable ion release was found in SS, PVC, and PE pipes. A kinetic model was postulated for the detected ion release with the mechanisms discussed in-depth.","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47980224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Jiang, Xiaoyi Xu, Wei Wu, Bin Wang, Yidong Sun, Xiaobin Chen, Zhengdong Shen, Tian-yin Huang
The quality of the water and the water environment in the estuary of a lake directly affect the water quality and ecological functions of the entire lake. Multi-technology systems, which integrate biotechnological analysis of a lake estuary and restoration of the ecological functions of the water in situ, have gradually been adopted for lake management and restoration. The Xielugang Estuary is located north of the Yangcheng Middle Lake and always exhibits a certain degree of eutrophic phenomena. To ensure the safety of the ecological environment in Yangcheng Lake, a multi-level purification and ecological system with ‘intercept precipitation–ecological restoration–coupled biological treatment’ was developed. Water quality monitoring results for the inlet and outlet of different units in the system from October 2020 to May 2021 showed that the system was effective. We also found that the purification capacity of the composite system was high and the system could significantly enhance the reduction of total nitrogen, total phosphorus, potassium permanganate index and total suspended solids. The average removal rates for these components were 41.34, 61.76, 35.21 and 67.21%, respectively, and the removal rate for typical heavy metals (Zn, Cu, Cd, and Pb) was 30.4–48.9%. The composite system substantially improved the water quality of the estuary and the wetland ecological function, demonstrating its effectiveness and significance.
{"title":"Analysis on the effect of large-scale compound ecological engineering system on pollution control of the estuary of a lake","authors":"Y. Jiang, Xiaoyi Xu, Wei Wu, Bin Wang, Yidong Sun, Xiaobin Chen, Zhengdong Shen, Tian-yin Huang","doi":"10.2166/wrd.2021.159","DOIUrl":"https://doi.org/10.2166/wrd.2021.159","url":null,"abstract":"\u0000 The quality of the water and the water environment in the estuary of a lake directly affect the water quality and ecological functions of the entire lake. Multi-technology systems, which integrate biotechnological analysis of a lake estuary and restoration of the ecological functions of the water in situ, have gradually been adopted for lake management and restoration. The Xielugang Estuary is located north of the Yangcheng Middle Lake and always exhibits a certain degree of eutrophic phenomena. To ensure the safety of the ecological environment in Yangcheng Lake, a multi-level purification and ecological system with ‘intercept precipitation–ecological restoration–coupled biological treatment’ was developed. Water quality monitoring results for the inlet and outlet of different units in the system from October 2020 to May 2021 showed that the system was effective. We also found that the purification capacity of the composite system was high and the system could significantly enhance the reduction of total nitrogen, total phosphorus, potassium permanganate index and total suspended solids. The average removal rates for these components were 41.34, 61.76, 35.21 and 67.21%, respectively, and the removal rate for typical heavy metals (Zn, Cu, Cd, and Pb) was 30.4–48.9%. The composite system substantially improved the water quality of the estuary and the wetland ecological function, demonstrating its effectiveness and significance.","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45692332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of powder-activated carbon pre-coating membrane on the performance of the UF system for wastewater reclamation: a pilot-scale study","authors":"Tong Yu, Haoshuai Yin, Lihua Cheng, X. Bi","doi":"10.2166/WRD.2021.063","DOIUrl":"https://doi.org/10.2166/WRD.2021.063","url":null,"abstract":"","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43481531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To explore the effects of mixed irrigation on soil and crops, a pot experiment was conducted in two salinity levels of brackish water, four levels of mixed brackish-reclaimed water and freshwater irrigation as the control. The soil Na-Cl to Ca-SO4 contents changed, and activities of soil alkaline phosphatase and polyphenol oxidase changed, exhibiting a ‘V’-shaped curve with increasing the proportion of reclaimed water in the mixture. At the same brackish-reclaimed water level, there were no significant differences in alkaline phosphatase and polyphenol oxidase activities except for soil alkaline phosphatase activity decreasing significantly with the increase in salinity under brackish water irrigation. Mixed irrigation obviously improved superoxide dismutase activity but no significant influences on aboveground dry weight, underground biomass or crop physiological indexes (chlorophyll, soluble protein, malondialdehyde, peroxidase, catalase). Based on the integrated biological response index version 2 (IBRv2), the deviation of reclaimed water irrigation was the smallest, followed by 1:1 and 1:2 (3, 5 g/L brackish water salinities, respectively), with IBRv2 values of 7.94, 12.55 and 16.04. Therefore, considering the soil-crop characteristics, limited daily water amount and inadequate pipeline facilities for reclaimed water, the brackish-reclaimed water ratio should be 1:1 and 1:2 at 3, 5 g/L of brackish water, respectively.
{"title":"Effects of mixed irrigation using brackish water with different salinities and reclaimed water on a soil-crop system","authors":"Chuncheng Liu, Bingjian Cui, Chao Hu, Haiqing Wu, Feng Gao","doi":"10.2166/wrd.2021.043","DOIUrl":"https://doi.org/10.2166/wrd.2021.043","url":null,"abstract":"\u0000 To explore the effects of mixed irrigation on soil and crops, a pot experiment was conducted in two salinity levels of brackish water, four levels of mixed brackish-reclaimed water and freshwater irrigation as the control. The soil Na-Cl to Ca-SO4 contents changed, and activities of soil alkaline phosphatase and polyphenol oxidase changed, exhibiting a ‘V’-shaped curve with increasing the proportion of reclaimed water in the mixture. At the same brackish-reclaimed water level, there were no significant differences in alkaline phosphatase and polyphenol oxidase activities except for soil alkaline phosphatase activity decreasing significantly with the increase in salinity under brackish water irrigation. Mixed irrigation obviously improved superoxide dismutase activity but no significant influences on aboveground dry weight, underground biomass or crop physiological indexes (chlorophyll, soluble protein, malondialdehyde, peroxidase, catalase). Based on the integrated biological response index version 2 (IBRv2), the deviation of reclaimed water irrigation was the smallest, followed by 1:1 and 1:2 (3, 5 g/L brackish water salinities, respectively), with IBRv2 values of 7.94, 12.55 and 16.04. Therefore, considering the soil-crop characteristics, limited daily water amount and inadequate pipeline facilities for reclaimed water, the brackish-reclaimed water ratio should be 1:1 and 1:2 at 3, 5 g/L of brackish water, respectively.","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44615925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Kehrein, M. Jafari, Marc Slagt, E. Cornelissen, P. Osseweijer, John Posada, M. V. van Loosdrecht
The objective of this paper is to compare, under Dutch market conditions, the energy consumption and net costs of membrane-based advanced treatment processes for three water reuse types (i.e. potable, industrial, agricultural reuse). The water source is municipal wastewater treatment plant effluent. Results indicate that the application of reverse osmosis is needed to reclaim high quality water for industrial and potable reuse but not for irrigation water which offers significant energy savings but may not lead automatically to lower net costs. While a reclamation process for industrial reuse is economically most promising, irrigation water reclamation processes are not cost effective due to low water prices. Moreover, process operational expenditures may exceed capital expenditures which is important for tender procedures. A significant cost factor is waste management that may exceed energy costs. Water recovery rates could be significantly enhanced through the integration of a softener/biostabilizer unit prior to reverse osmosis. Moreover, the energy consumption of wastewater reclamation processes could be supplied on-site with solar energy. The possibility of designing a ‘fit for multi-purpose’ reclamation process is discussed briefly. This comparative analysis allows for better informed decision making about which reuse type is preferably targeted in a municipal wastewater reuse project from a process design perspective.
{"title":"A techno-economic analysis of membrane-based advanced treatment processes for the reuse of municipal wastewater","authors":"P. Kehrein, M. Jafari, Marc Slagt, E. Cornelissen, P. Osseweijer, John Posada, M. V. van Loosdrecht","doi":"10.2166/wrd.2021.016","DOIUrl":"https://doi.org/10.2166/wrd.2021.016","url":null,"abstract":"\u0000 The objective of this paper is to compare, under Dutch market conditions, the energy consumption and net costs of membrane-based advanced treatment processes for three water reuse types (i.e. potable, industrial, agricultural reuse). The water source is municipal wastewater treatment plant effluent. Results indicate that the application of reverse osmosis is needed to reclaim high quality water for industrial and potable reuse but not for irrigation water which offers significant energy savings but may not lead automatically to lower net costs. While a reclamation process for industrial reuse is economically most promising, irrigation water reclamation processes are not cost effective due to low water prices. Moreover, process operational expenditures may exceed capital expenditures which is important for tender procedures. A significant cost factor is waste management that may exceed energy costs. Water recovery rates could be significantly enhanced through the integration of a softener/biostabilizer unit prior to reverse osmosis. Moreover, the energy consumption of wastewater reclamation processes could be supplied on-site with solar energy. The possibility of designing a ‘fit for multi-purpose’ reclamation process is discussed briefly. This comparative analysis allows for better informed decision making about which reuse type is preferably targeted in a municipal wastewater reuse project from a process design perspective.","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42700194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chen-yan Hu, Si-Cheng Ren, Yi-Li Lin, Ji-Chen Zhang, Ye-Ye Zhu, Cun Xiong, Qiang Wang
In this study, we studied the degradation kinetics of a common iodine contrast agent, diatrizoate, by ozone and the formation of disinfection by-products (DBPs) in the sequential chlorination. Effects of ozone concentration, solution pH, and bromide concentration on diatrizoate degradation were evaluated. The results indicate that diatrizoate can be effectively degraded (over 80% within 1 h) by ozone, and the degradation kinetics can be well described using the pseudo-first-order kinetic model. The pseudo-first-order rate constant (kobs) of diatrizoate degradation significantly increased with increasing ozone concentration and decreasing bromide concentration. The kobs kept increasing with the increase of pH value and reached a maximum of 6.5 (±0.05) × 10−2 min−1 at pH 9. As the ozone concentration gradually increased from 0.342 to 1.316 mg/L, the corresponding kobs of diatrizoate degradation increased from 1.76 (±0.20) × 10−3 to 4.22 (±0.3) × 10−2 min−1. The bromide concentration exhibited a strong inhibitory effect on diatrizoate degradation because of the competition for ozone with diatrizoate. Trichloromethane was the only detected DBP in the subsequent chlorination in the absence of bromide. However, in the presence of bromide, six other DBPs were detected, and bromochloroiodomethane and tribromomethane became the major products with concentrations 1–2 orders higher than those of the other DBPs. In order to provide safe drinking water to the public, water should be maintained at circumneutral pH values and low bromine concentrations (<5 μM) before reaching the chlorine disinfection process to effectively control the formation of DBPs.
{"title":"Kinetics of diatrizoate degradation by ozone and the formation of disinfection by-products in the sequential chlorination","authors":"Chen-yan Hu, Si-Cheng Ren, Yi-Li Lin, Ji-Chen Zhang, Ye-Ye Zhu, Cun Xiong, Qiang Wang","doi":"10.2166/wrd.2021.053","DOIUrl":"https://doi.org/10.2166/wrd.2021.053","url":null,"abstract":"\u0000 In this study, we studied the degradation kinetics of a common iodine contrast agent, diatrizoate, by ozone and the formation of disinfection by-products (DBPs) in the sequential chlorination. Effects of ozone concentration, solution pH, and bromide concentration on diatrizoate degradation were evaluated. The results indicate that diatrizoate can be effectively degraded (over 80% within 1 h) by ozone, and the degradation kinetics can be well described using the pseudo-first-order kinetic model. The pseudo-first-order rate constant (kobs) of diatrizoate degradation significantly increased with increasing ozone concentration and decreasing bromide concentration. The kobs kept increasing with the increase of pH value and reached a maximum of 6.5 (±0.05) × 10−2 min−1 at pH 9. As the ozone concentration gradually increased from 0.342 to 1.316 mg/L, the corresponding kobs of diatrizoate degradation increased from 1.76 (±0.20) × 10−3 to 4.22 (±0.3) × 10−2 min−1. The bromide concentration exhibited a strong inhibitory effect on diatrizoate degradation because of the competition for ozone with diatrizoate. Trichloromethane was the only detected DBP in the subsequent chlorination in the absence of bromide. However, in the presence of bromide, six other DBPs were detected, and bromochloroiodomethane and tribromomethane became the major products with concentrations 1–2 orders higher than those of the other DBPs. In order to provide safe drinking water to the public, water should be maintained at circumneutral pH values and low bromine concentrations (<5 μM) before reaching the chlorine disinfection process to effectively control the formation of DBPs.","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48920203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Jiang, Liqin Han, Juntian Wang, Chang Lu, Pan Yang, Yanlei Tan, C. Shuang, Dong Chen, Aimin Li
A Co/Ti electrode for nitrate reduction was prepared by electrode-deposition. In the single-compartment electrolysis cell, nitrate (100 mg/L) removal reached nearly 100% after 3 h electrolysis under the current density of 20 mA cm–2 by using the Co/Ti electrode as cathode, and the main reduction products were ammonium nitrogen (66.5%) and nitrogen gas (33.5%). This performance on nitrate removal was comparable to a Co3O4/Ti electrode, and the electroactivity of the Co/Ti electrode towards nitrite reduction was higher than that of a Co3O4/Ti electrode. The Co/Ti electrode exhibited an improved stability with 18.7% of mass loss and 25.5% of Co dissolution compared with the Co3O4/Ti electrode after ultrasonic interference. The presence of chlorine ion (1,000 mg/L) could promote the total nitrogen (TN) removal to approximately 100% after 3 h electrolysis because of the ammonium oxidation by the free chlorine produced from the anode. In the presence of calcium (50 mg/L) and phosphate (0.5 mg/L), the nitrate removal decreased from 85.4 ± 1.5 to 57.7 ± 3.5% after ten reuse cycles. This result suggests that Ca and P should be pre-removed before the electro-reduction of nitrate.
采用电极沉积法制备了一种用于硝酸盐还原的钴/钛电极。在单室电解槽中,以Co/Ti电极为阴极,在20 mA cm–2的电流密度下电解3小时后,硝酸盐(100 mg/L)的去除率接近100%,主要还原产物为铵态氮(66.5%)和氮气(33.5%)。这种硝酸盐去除性能与Co3O4/Ti电极相当,并且Co/Ti电极对亚硝酸盐还原的电活性高于Co3O4/Ti电极的电活性。在超声干扰后,与Co3O4/Ti电极相比,Co/Ti电极表现出18.7%的质量损失和25.5%的Co溶解的改进的稳定性。氯离子(1000mg/L)的存在可以在电解3h后将总氮(TN)的去除率提高到约100%,因为阳极产生的游离氯会氧化铵。在钙(50mg/L)和磷酸盐(0.5mg/L)存在的情况下,10个重复使用周期后,硝酸盐的去除率从85.4±1.5%下降到57.7±3.5%。这一结果表明,在硝酸盐的电还原之前,应预先去除Ca和P。
{"title":"Preparation of Co/Ti electrode by electro-deposition for aqueous nitrate reduction","authors":"B. Jiang, Liqin Han, Juntian Wang, Chang Lu, Pan Yang, Yanlei Tan, C. Shuang, Dong Chen, Aimin Li","doi":"10.2166/wrd.2021.047","DOIUrl":"https://doi.org/10.2166/wrd.2021.047","url":null,"abstract":"\u0000 A Co/Ti electrode for nitrate reduction was prepared by electrode-deposition. In the single-compartment electrolysis cell, nitrate (100 mg/L) removal reached nearly 100% after 3 h electrolysis under the current density of 20 mA cm–2 by using the Co/Ti electrode as cathode, and the main reduction products were ammonium nitrogen (66.5%) and nitrogen gas (33.5%). This performance on nitrate removal was comparable to a Co3O4/Ti electrode, and the electroactivity of the Co/Ti electrode towards nitrite reduction was higher than that of a Co3O4/Ti electrode. The Co/Ti electrode exhibited an improved stability with 18.7% of mass loss and 25.5% of Co dissolution compared with the Co3O4/Ti electrode after ultrasonic interference. The presence of chlorine ion (1,000 mg/L) could promote the total nitrogen (TN) removal to approximately 100% after 3 h electrolysis because of the ammonium oxidation by the free chlorine produced from the anode. In the presence of calcium (50 mg/L) and phosphate (0.5 mg/L), the nitrate removal decreased from 85.4 ± 1.5 to 57.7 ± 3.5% after ten reuse cycles. This result suggests that Ca and P should be pre-removed before the electro-reduction of nitrate.","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47760513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mengmeng Yi, Chun Wang, He Wang, Xi Zhu, Zhigang Liu, F. Gao, X. Ke, Jianmeng Cao, Miao Wang, Ying Liu, Mai-xin Lu
In the present study, we investigated the effect of probiotics immobilized by oyster shells (Os), vesuvianite (Ve) and walnut shells (Ws) on the remediation of aquaculture water and sediment by analyzing the variation of ammonia-nitrogen (NH4–N), nitrate-nitrogen (NO3–N), nitrite-nitrogen (NO2–N), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (CODCr), as well as the microbiota of the water and sediment. The positive or negative effects of the treatment groups on the water quality parameters were both observed. Compared with their effects on water quality parameters, the treatment groups had better effects on sediment parameters. Group Ve had the best remediation effect of NH4–N and NO3–N in the sediment (decreased by 5.22 and 1.66 times, respectively). Group Os showed a lower relative concentration of TN and CODCr (decreased by 3.77 and 0.95 times, respectively). The high-throughput sequencing results revealed that the immobilized probiotics increased the relative abundances of functional bacteria in the treatment groups at the phylum and genus level. The above results showed that probiotics immobilized by oyster shells, vesuvianite and walnut shells positively affected the aquaculture environment's remediation, especially the sediment.
{"title":"The in situ remediation of aquaculture water and sediment by commercial probiotics immobilized on different carriers","authors":"Mengmeng Yi, Chun Wang, He Wang, Xi Zhu, Zhigang Liu, F. Gao, X. Ke, Jianmeng Cao, Miao Wang, Ying Liu, Mai-xin Lu","doi":"10.2166/wrd.2021.049","DOIUrl":"https://doi.org/10.2166/wrd.2021.049","url":null,"abstract":"\u0000 In the present study, we investigated the effect of probiotics immobilized by oyster shells (Os), vesuvianite (Ve) and walnut shells (Ws) on the remediation of aquaculture water and sediment by analyzing the variation of ammonia-nitrogen (NH4–N), nitrate-nitrogen (NO3–N), nitrite-nitrogen (NO2–N), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (CODCr), as well as the microbiota of the water and sediment. The positive or negative effects of the treatment groups on the water quality parameters were both observed. Compared with their effects on water quality parameters, the treatment groups had better effects on sediment parameters. Group Ve had the best remediation effect of NH4–N and NO3–N in the sediment (decreased by 5.22 and 1.66 times, respectively). Group Os showed a lower relative concentration of TN and CODCr (decreased by 3.77 and 0.95 times, respectively). The high-throughput sequencing results revealed that the immobilized probiotics increased the relative abundances of functional bacteria in the treatment groups at the phylum and genus level. The above results showed that probiotics immobilized by oyster shells, vesuvianite and walnut shells positively affected the aquaculture environment's remediation, especially the sediment.","PeriodicalId":17556,"journal":{"name":"Journal of Water Reuse and Desalination","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2021-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43838722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}